STRATOS initiative

The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodological developments are ignored in practice. Consequently, design and analysis of observational studies often exhibit serious weaknesses. The lack of guidance on vital practical issues discourages many applied researchers from using more sophisticated and possibly more appropriate methods when analyzing observational studies. Furthermore, many analyses are conducted by researchers with a relatively weak statistical background and limited experience in using statistical methodology and software. Consequently, even ‘standard’ analyses reported in the medical literature are often flawed, casting doubt on their results and conclusions. An efficient way to help researchers to keep up with recent methodological developments is to develop guidance documents that are spread to the research community at large.

These observations led to the initiation of the STRATOS (STRengthening Analytical Thinking for Observational Studies) initiative, a large collaboration of experts in many different areas of biostatistical research. The objective of STRATOS is to provide accessible and accurate guidance in the design and analysis of observational studies. The guidance is intended for applied statisticians and other data analysts with varying levels of statistical education, experience and interests (click to enlarge).

The Steering Group has decided to start with seven topics of general interest. Two topic groups were added later. Guidance documents will be developed by separate topic groups (TGs), each comprising experts in different area of statistical methodology, alongside applied researchers who may represent future end-users of the STRATOS documents. Each TG will start by developing guidance aimed primarily at level 2 statistical knowledge, which is perhaps slightly below state of the art. STRATOS structure and the initial road map (click to enlarge). The STRATOS initiative is closely connected to the International Society of Clinical Biostatistics (ISCB) and was launched at a half-day Mini-Symposium on the last day of the ISCB meeting in Munich, in August 2013.


To co-ordinate the initiative, to share best research practices and to disseminate research tools and results from the work of the topic groups (TG), several cross-cutting panels have been started recently. They aim to develop recommendations (sometimes rather loose as for simulation studies, sometimes more strict as for STRATOS publications) and to provide the infrastructure for those aspects of the initiative that apply to all or most of the TGs, and to coordination of the efforts of the individual TGs. Recommendations aim to support, simplify and harmonize work within and across the TGs. They will also help increase transparency in deriving guidance documents in STRATOS.

The following Panels have been created to date:

Chairs: James Carpenter, Willi Sauerbrei
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Chairs: Bianca De Stavola, Pamela Shaw
Co-Chairs: Mitchell Gail, Petra Macaskill
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Chairs: Martin Boeker, Marianne Huebner
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Chairs: Joerg Rahnenfuehrer, Willi Sauerbrei
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Literature Review
Chairs: Gary Collins, Carl Moons
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Simulation Studies
Chairs: Michal Abrahamowicz, Anne-Laure Boulesteix
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Data Sets
Chairs: Saskia Le Cessie, Maarten van Smeden
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Knowledge Translation
Chair: Suzanne Cadarette
Co-Chair: Catherine Quantin
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Contact Organizations
Chairs: Willi Sauerbrei
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Chair: Mark Baillie
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